bug#23369: 25.0.93; CANNOT_DUMP build fails if resizing terminal during startup in tty mode

[Eli Zaretskii <eliz@gnu.org>]

> From: Glenn Morris <rgm@gnu.org>
> Cc: fredrik@fornwall.net,  23369@debbugs.gnu.org
> Date: Wed, 27 Apr 2016 17:01:13 -0400
> 
> Anyway, I managed to get a useful backtrace, which revealed the real
> problem, and a trivial fix:
> 
> Lisp Backtrace:
>   "frames-on-display-list" (0xffff17e0)
>   "let" (0xffff19d0)
>   "mapcar" (0xffff1d50)
>   "apply" (0xffff1ed0)
>   "cons" (0xffff1ff0)
>   "internal--before-save-selected-window" (0xffff2160)
>   "let" (0xffff2450)
>   "save-selected-window" (0xffff2570)
>   "walk-windows" (0xffff26e0)
>   "let" (0xffff2a20)
>   "window--process-window-list" (0xffff2b90)
>   "let" (0xffff2e80)
>   "dolist" (0xffff2fa0)
>   "window--adjust-process-windows" (0xffff31e0)
>   "load" (0xffff3800)
>  
> *** a/lisp/window.el
> --- b/lisp/window.el
> ***************
> *** 8520,8525 ****
> --- 8520,8526 ----
>   displaying that processes's buffer."
>     (let ((processes (process-list))
>           (process-windows nil))
> +     (when processes
>         (walk-windows
>          (lambda (window)
>            (let ((buffer (window-buffer window))
> ***************
> *** 8538,8544 ****
>                           nil)
>                       (setf iter (cdr iter)))))))
>        1 t)
> !     process-windows))
>   
>   (defun window--adjust-process-windows ()
>     "Update process window sizes to match the current window configuration."
> --- 8539,8545 ----
>                             nil)
>                         (setf iter (cdr iter)))))))
>          1 t)
> !       process-windows)))
>   
>   (defun window--adjust-process-windows ()
>     "Update process window sizes to match the current window configuration."
> 

Thanks.

> > But the error message is actually quite informative; at the very
> > least, it tells where the problem happened, and frequently also names
> > the guilty function or variable.
> 
> I feel like we are miscommunicating.
> 
> Neither of the errors mentioned in the original report (NSTATICS,
> internal-echo-keystrokes-prefix) have anything to do with the real
> problem. They are just noise caused by an Emacs with half its loadup
> missing falling through to the command-loop and inevitably failing
> miserably. This is not informative. If there is an error loading loadup,
> it should print it and abort. (I see I am repeating
> http://debbugs.gnu.org/22975#38 ).

We have different experiences.  Those messages did help me when I was
debugging similar problems.  (I see I am repeating
http://debbugs.gnu.org/22975#44 ).